Mill and drill pad fasteners are commonly used in newer vehicle production for the attachment of polymeric body components to vehicle subassemblies. Traditional mill and drill pad fasteners are currently manufactured by using an extruded metal sheet configured to create a metal reinforcing band into which an epoxy or polyvinyl resin such as polyvinylchloride (PVC) is molded.
There are two main problems with the current mill and drill pad fastener. First, as self-tapping screws are inserted and screwed into the epoxy or PVC resin, the polymeric component of the fasteners tends to crack when a torque in excess of 5-5.5 Newton-meters is applied to the screw in the fastener.
And second, there is a problem in the ability to mill the fastener to the desired height. Since rarely is a vehicle assembled perfectly centered on its axis, there is the need to mill the fasteners to the desired height. With traditional fasteners, the presence of a reinforced metal band, which surrounds the polymeric pad, causes a rapid deterioration of the cutting edge of the milling tools used.